National Instruments 800 Series 사용자 설명서

You can use switch S7 to terminate the external trigger input SMB 
with 50 

Ω

 to ground. Figure 3-7a shows the default setting for a 

non-terminated trigger input SMB. Use the setting of Figure 3-7b to 
terminate the trigger input SMB. Switch S7 is located above switches 
S4, S5, and S6, which have no effect on this configuration.

Figure 3-7.  SMB Trigger Input Termination

The VXIpc-800 has an onboard EEPROM, which stores default register 
values for the VXI circuitry. These values are loaded when you power 
up the computer. These values read from the EEPROM tell the PCI 
interface of the VXIbus registers so that the VXI interface is ready to 
respond to Resource Manager accesses within the required 5 s of 
SYSRST* deasserting. You can use switch S2 to disable this power-on 
self-configuration (POSC) circuit. Although this makes the VXI 
circuitry unusable, it is sometimes helpful in debugging address and 
interrupt conflicts with add-in boards. In general, however, you should 
leave switch S2 in its factory-default setting. Figure 3-8 shows the 
possible configurations for S2.

Figure 3-8.  Power-On Self Configuration Status

S7

S7

a. Does Not Terminate

Trigger Input (Default)

b. Terminate Trigger Input

S2

S2

a. VXI Circuitry Loads Power-on

Defaults from EEPROM (Default)

b. Power-on Self Configuration

Circuit is Disabled